[vimscript] Update name in credits

[dbarnett]

[dbarnett]

@artemispax @malcolmr FYI

[JaphyFan]

你好，你的邮件已收到,我会尽快回复。祝你工作顺利，生活愉快！

[artasparks]

Thanks!

[dbarnett]

Okay to apply this one change manually?

I already made the corresponding changes on the internal copy, hoping to manually apply them here for now, and in parallel work on setting up tooling to automatically sync changes from Google internal copy to here.